This invention generally relates to hunting bullets and more particularly to a bullet having a hollow point.
Hunting bullets are generally small caliber, i.e. less than 0.50 caliber. They generally have a hollow point or soft metal nose portion to enhance energy absorption within the target animal tissue. Lead hollow point bullets have been marketed successfully for years. Lead hollow point bullets have one serious drawback. They all tend to upset and expand greatly within a short penetration distance and are not suitable for deep penetration. A hollow point, jacketed mushrooming bullet is disclosed in U.S. Pat. No. 1,633,168.
Soft point bullets such as the well know Nosler partition bullet, disclosed in U.S. Pat. No. 3,003,420 are utilized where deep penetration is required. Current soft point bullets expose lead and lead oxidation products to the environment after expansion.
Hunting bullets made primarily of a metal harder than lead have also been produced in order to achieve deep penetration with maximum tissue cutting action without splintering the bullet into pieces. For example, in U.S. Pat. No. 4,044,685, a jacketless bullet having a solid cylindrical copper alloy portion and a hollow nose portion filled with lead or other plastic deformable material is disclosed. This bullet is basically a hard metal hollow point bullet with axial grooves in the interior walls of the lead filled hollow point to provide sharp cutting flags during expansion in the target. These flags enhance cutting of the surrounding tissue as the expanding projectile passes through. This prior art bullet design suffers from having a reduced mass due to the absence of lead in the body of the projectile which limits its impact energy. In addition, it carries a substantial amount of lead in the nose which is exposed to the environment and can wash off upon expansion.
Another recent U.S. Pat. No., 4,655,140 discloses a partition type bullet similar to the Nosler partition bullet mentioned above. The hollow nose has oblique grooves in the outer surface of the ogive. A lead insert is disposed in the nose and a lead core is provided behind a central partition portion of the copper alloy partition bullet. Again, the lead disposed in the nose of the bullet is externally exposed upon expansion and deforms or upsets in a conventional manner upon impact. Further, the lead core behind the partition is exposed to the environment to the rear. Thus, upon impact in a target animal, a substantial amount of lead is exposed as well as washed into the adjacent tissues during bullet passage.
A lead-free bullet for hunting is disclosed in U.S. Pat. No. 4,685,397. This bullet is a solid one piece hollow point projectile made of tombac or copper. Closing the front end of the blind bore in the nose of the projectile is a steel plug which has wedge shaped ribs. Upon expansion, the steel plug is forced rearward into the central bore. The ribs cause the nose portion to split and curl backwards as curling petals which provide multiple cutting surfaces to lacerate tissue. However, this bullet has low mass and insufficient mass for deep penetration within a target.
Accordingly, there is still a need for a deep penetrating expanding bullet that does not permit exposure of lead while still providing substantial tissue damage.
Accordingly, it is an object of the present invention to provide a small caliber bullet which minimizes the potential of airborne environmental lead contamination.
It is another object of the present invention to provide a bullet with an encapsulated lead core which minimizes contamination of animal tissue by eliminating lead exposure, lead wash and jacket fragmentation.
It is a still further object of the present invention to provide a small caliber bullet which has no frontal lead wash during expansion.
It is a still further object of the present invention to provide a small caliber bullet which has improved impact trauma associated with penetration of the bullet into soft body tissue.